Combination therapy of peginterferon and ribavirin for chronic hepatitis C patients with genotype 1b and low-virus load

Hepatitis C genotype 1 virus with low viral load and rapid virologic response to peginterferon/ribavirin obviates a protease inhibitor

The new standard of care for treatment-naïve patients with hepatitis C virus (HCV) genotype 1 includes triple therapy with peginterferon, ribavirin, and a protease inhibitor. However, patients who achieve a rapid virologic response after 4 weeks of peginterferon and ribavirin therapy are likely to achieve a sustained virologic response (SVR), and we hypothesized that protease inhibitor therapy may be unnecessary in these patients. Treatment-naïve, noncirrhosis patients infected with genotype-1 HCV and a low viral load at baseline were considered for inclusion (n = 233). After 4 weeks of lead-in therapy with peginterferon α-2b and ribavirin, 101 patients (48%) had a rapid virologic response (defined as undetectable levels of hepatitis C virus RNA at 4 weeks) and were eligible to participate. Patients were randomized 1:1 to 20 weeks of additional therapy with peginterferon α-2b and ribavirin (double therapy) or to 24 weeks of peginterferon α-2b, ribavirin, and boceprevir (triple therapy). There was no significant difference in rates of SVR-12 in patients treated with double versus triple therapy. This similarity persisted regardless of viral subtype (genotype 1a or 1b), interleukin (IL)-28b genotype (CC or non-CC), or ethnicity (African American versus non-Hispanic white).

CONCLUSION

Protease inhibitor therapy could be obviated in genotype 1-infected treatment-naïve patients with low viral load at baseline who achieve undetectable viremia after 4 weeks of peginterferon/ribavirin.

Pegylated interferon monotherapy in patients with chronic hepatitis C with low viremia and its relationship to mutations in the NS5A region and the single nucleotide polymorphism of interleukin-28B

AIM

Previous studies have suggested that patients with chronic hepatitis C with a low pretreatment hepatitis C virus (HCV) level have a high sustained virological response (SVR) rate, and that there would be a subpopulation of patients in which HCV can be eradicated with pegylated interferon (PEG IFN) alone without a decrease in SVR. However, the efficacy of PEG IFN monotherapy in patients with low HCV RNA levels is unclear. Several studies have reported that interferon sensitivity-determining region (ISDR) and the single-nucleotide polymorphism (SNP) of interleukin-28B (IL-28B) contribute to IFN response, but these relationships are controversial. The aim of this study was to determine whether the SNP of IL-28B (rs8099917) and amino acid substitutions in the ISDR among patients with low HCV levels affect the response to PEG IFN monotherapy.

METHODS

One hundred and four patients with low-level HCV infection were studied. Low HCV level was defined as 100 KIU/mL or less.

RESULTS

SVR was achieved in 94 patients (92.2%). HCV levels (≤50 KIU/mL) and ISDR (≥2 mutations) were associated with SVR on univariate analysis. The rates of SVR in the patients with IL-28B genotypes TT, TG and GG were 94.5%, 77.8% and 100%, respectively. The G allele tended to be associated with poor response to IFN therapy (P = 0.0623). On multivariate analysis, the ISDR was the factor predictive of SVR (P = 0.004).

CONCLUSION

The ISDR is significantly associated with a good response to PEG IFN monotherapy in patients with low HCV levels.

Very low viral load (VLVL) relapse following treatment of naïve patients with chronic hepatitis C

BACKGROUND

Sustained virologic response (SVR) to treatment of naïve patients with chronic hepatitis C (HCV) with pegylated interferon and ribavirin is 50-60%. Patients who relapse have a poor response to re-treatment. We report a group of relapse patients with SVR to low-dose re-treatment after 6 months.

AIM

Characterization of HCV relapse patients with very low viral load (VLVL) (HCV RNA <5,000 IU/ml) 6 months after stopping full-dose initial treatment.

METHODS

We identified 120 consecutive naïve patients over 4 years treated with pegylated interferon alpha-2a and ribavirin with full-dose therapy for 24 weeks (non-genotype 1) or 48 weeks (genotype 1) with baseline liver biopsy and at least 6 months of follow-up after treatment. HCV RNA by PCR and hepatic blood tests were obtained monthly during treatment and at least 1, 3, and 6 months post treatment.

RESULTS

Of the initially treated patients, 54.2% had SVR, 25% non-response and 20.8% relapsed. Four of 25 who relapsed (16%) and one similar patient referred to our program had HCV RNA <5,000 IU/ml 6 months after stopping treatment (VLVL relapse). Significant differences (P < 0.05) compared with the 21 other relapse patients included all five patients who were genotype 1; 4/5 had cirrhosis, baseline HCV RNA was lower, and all had SVR to less intensive re-treatment for 6 months.

CONCLUSION

VLVL relapse patients should be sought, because SVR to re-treatment is common despite genotype 1 cirrhosis.